Update prebuilt Clang to r365631c1 from Android.
The version we had was segfaulting.
Bug: 132420445
Change-Id: Icb45a6fe0b4e2166f7895e669df1157cec9fb4e0
diff --git a/linux-x64/clang/include/llvm/Bitstream/BitstreamReader.h b/linux-x64/clang/include/llvm/Bitstream/BitstreamReader.h
new file mode 100644
index 0000000..ccb4a49
--- /dev/null
+++ b/linux-x64/clang/include/llvm/Bitstream/BitstreamReader.h
@@ -0,0 +1,553 @@
+//===- BitstreamReader.h - Low-level bitstream reader interface -*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This header defines the BitstreamReader class. This class can be used to
+// read an arbitrary bitstream, regardless of its contents.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_BITSTREAM_BITSTREAMREADER_H
+#define LLVM_BITSTREAM_BITSTREAMREADER_H
+
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/Bitstream/BitCodes.h"
+#include "llvm/Support/Endian.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include <algorithm>
+#include <cassert>
+#include <climits>
+#include <cstddef>
+#include <cstdint>
+#include <memory>
+#include <string>
+#include <utility>
+#include <vector>
+
+namespace llvm {
+
+/// This class maintains the abbreviations read from a block info block.
+class BitstreamBlockInfo {
+public:
+ /// This contains information emitted to BLOCKINFO_BLOCK blocks. These
+ /// describe abbreviations that all blocks of the specified ID inherit.
+ struct BlockInfo {
+ unsigned BlockID;
+ std::vector<std::shared_ptr<BitCodeAbbrev>> Abbrevs;
+ std::string Name;
+ std::vector<std::pair<unsigned, std::string>> RecordNames;
+ };
+
+private:
+ std::vector<BlockInfo> BlockInfoRecords;
+
+public:
+ /// If there is block info for the specified ID, return it, otherwise return
+ /// null.
+ const BlockInfo *getBlockInfo(unsigned BlockID) const {
+ // Common case, the most recent entry matches BlockID.
+ if (!BlockInfoRecords.empty() && BlockInfoRecords.back().BlockID == BlockID)
+ return &BlockInfoRecords.back();
+
+ for (unsigned i = 0, e = static_cast<unsigned>(BlockInfoRecords.size());
+ i != e; ++i)
+ if (BlockInfoRecords[i].BlockID == BlockID)
+ return &BlockInfoRecords[i];
+ return nullptr;
+ }
+
+ BlockInfo &getOrCreateBlockInfo(unsigned BlockID) {
+ if (const BlockInfo *BI = getBlockInfo(BlockID))
+ return *const_cast<BlockInfo*>(BI);
+
+ // Otherwise, add a new record.
+ BlockInfoRecords.emplace_back();
+ BlockInfoRecords.back().BlockID = BlockID;
+ return BlockInfoRecords.back();
+ }
+};
+
+/// This represents a position within a bitstream. There may be multiple
+/// independent cursors reading within one bitstream, each maintaining their
+/// own local state.
+class SimpleBitstreamCursor {
+ ArrayRef<uint8_t> BitcodeBytes;
+ size_t NextChar = 0;
+
+public:
+ /// This is the current data we have pulled from the stream but have not
+ /// returned to the client. This is specifically and intentionally defined to
+ /// follow the word size of the host machine for efficiency. We use word_t in
+ /// places that are aware of this to make it perfectly explicit what is going
+ /// on.
+ using word_t = size_t;
+
+private:
+ word_t CurWord = 0;
+
+ /// This is the number of bits in CurWord that are valid. This is always from
+ /// [0...bits_of(size_t)-1] inclusive.
+ unsigned BitsInCurWord = 0;
+
+public:
+ static const constexpr size_t MaxChunkSize = sizeof(word_t) * 8;
+
+ SimpleBitstreamCursor() = default;
+ explicit SimpleBitstreamCursor(ArrayRef<uint8_t> BitcodeBytes)
+ : BitcodeBytes(BitcodeBytes) {}
+ explicit SimpleBitstreamCursor(StringRef BitcodeBytes)
+ : BitcodeBytes(arrayRefFromStringRef(BitcodeBytes)) {}
+ explicit SimpleBitstreamCursor(MemoryBufferRef BitcodeBytes)
+ : SimpleBitstreamCursor(BitcodeBytes.getBuffer()) {}
+
+ bool canSkipToPos(size_t pos) const {
+ // pos can be skipped to if it is a valid address or one byte past the end.
+ return pos <= BitcodeBytes.size();
+ }
+
+ bool AtEndOfStream() {
+ return BitsInCurWord == 0 && BitcodeBytes.size() <= NextChar;
+ }
+
+ /// Return the bit # of the bit we are reading.
+ uint64_t GetCurrentBitNo() const {
+ return NextChar*CHAR_BIT - BitsInCurWord;
+ }
+
+ // Return the byte # of the current bit.
+ uint64_t getCurrentByteNo() const { return GetCurrentBitNo() / 8; }
+
+ ArrayRef<uint8_t> getBitcodeBytes() const { return BitcodeBytes; }
+
+ /// Reset the stream to the specified bit number.
+ Error JumpToBit(uint64_t BitNo) {
+ size_t ByteNo = size_t(BitNo/8) & ~(sizeof(word_t)-1);
+ unsigned WordBitNo = unsigned(BitNo & (sizeof(word_t)*8-1));
+ assert(canSkipToPos(ByteNo) && "Invalid location");
+
+ // Move the cursor to the right word.
+ NextChar = ByteNo;
+ BitsInCurWord = 0;
+
+ // Skip over any bits that are already consumed.
+ if (WordBitNo) {
+ if (Expected<word_t> Res = Read(WordBitNo))
+ return Error::success();
+ else
+ return Res.takeError();
+ }
+
+ return Error::success();
+ }
+
+ /// Get a pointer into the bitstream at the specified byte offset.
+ const uint8_t *getPointerToByte(uint64_t ByteNo, uint64_t NumBytes) {
+ return BitcodeBytes.data() + ByteNo;
+ }
+
+ /// Get a pointer into the bitstream at the specified bit offset.
+ ///
+ /// The bit offset must be on a byte boundary.
+ const uint8_t *getPointerToBit(uint64_t BitNo, uint64_t NumBytes) {
+ assert(!(BitNo % 8) && "Expected bit on byte boundary");
+ return getPointerToByte(BitNo / 8, NumBytes);
+ }
+
+ Error fillCurWord() {
+ if (NextChar >= BitcodeBytes.size())
+ return createStringError(std::errc::io_error,
+ "Unexpected end of file reading %u of %u bytes",
+ NextChar, BitcodeBytes.size());
+
+ // Read the next word from the stream.
+ const uint8_t *NextCharPtr = BitcodeBytes.data() + NextChar;
+ unsigned BytesRead;
+ if (BitcodeBytes.size() >= NextChar + sizeof(word_t)) {
+ BytesRead = sizeof(word_t);
+ CurWord =
+ support::endian::read<word_t, support::little, support::unaligned>(
+ NextCharPtr);
+ } else {
+ // Short read.
+ BytesRead = BitcodeBytes.size() - NextChar;
+ CurWord = 0;
+ for (unsigned B = 0; B != BytesRead; ++B)
+ CurWord |= uint64_t(NextCharPtr[B]) << (B * 8);
+ }
+ NextChar += BytesRead;
+ BitsInCurWord = BytesRead * 8;
+ return Error::success();
+ }
+
+ Expected<word_t> Read(unsigned NumBits) {
+ static const unsigned BitsInWord = MaxChunkSize;
+
+ assert(NumBits && NumBits <= BitsInWord &&
+ "Cannot return zero or more than BitsInWord bits!");
+
+ static const unsigned Mask = sizeof(word_t) > 4 ? 0x3f : 0x1f;
+
+ // If the field is fully contained by CurWord, return it quickly.
+ if (BitsInCurWord >= NumBits) {
+ word_t R = CurWord & (~word_t(0) >> (BitsInWord - NumBits));
+
+ // Use a mask to avoid undefined behavior.
+ CurWord >>= (NumBits & Mask);
+
+ BitsInCurWord -= NumBits;
+ return R;
+ }
+
+ word_t R = BitsInCurWord ? CurWord : 0;
+ unsigned BitsLeft = NumBits - BitsInCurWord;
+
+ if (Error fillResult = fillCurWord())
+ return std::move(fillResult);
+
+ // If we run out of data, abort.
+ if (BitsLeft > BitsInCurWord)
+ return createStringError(std::errc::io_error,
+ "Unexpected end of file reading %u of %u bits",
+ BitsInCurWord, BitsLeft);
+
+ word_t R2 = CurWord & (~word_t(0) >> (BitsInWord - BitsLeft));
+
+ // Use a mask to avoid undefined behavior.
+ CurWord >>= (BitsLeft & Mask);
+
+ BitsInCurWord -= BitsLeft;
+
+ R |= R2 << (NumBits - BitsLeft);
+
+ return R;
+ }
+
+ Expected<uint32_t> ReadVBR(unsigned NumBits) {
+ Expected<unsigned> MaybeRead = Read(NumBits);
+ if (!MaybeRead)
+ return MaybeRead;
+ uint32_t Piece = MaybeRead.get();
+
+ if ((Piece & (1U << (NumBits-1))) == 0)
+ return Piece;
+
+ uint32_t Result = 0;
+ unsigned NextBit = 0;
+ while (true) {
+ Result |= (Piece & ((1U << (NumBits-1))-1)) << NextBit;
+
+ if ((Piece & (1U << (NumBits-1))) == 0)
+ return Result;
+
+ NextBit += NumBits-1;
+ MaybeRead = Read(NumBits);
+ if (!MaybeRead)
+ return MaybeRead;
+ Piece = MaybeRead.get();
+ }
+ }
+
+ // Read a VBR that may have a value up to 64-bits in size. The chunk size of
+ // the VBR must still be <= 32 bits though.
+ Expected<uint64_t> ReadVBR64(unsigned NumBits) {
+ Expected<uint64_t> MaybeRead = Read(NumBits);
+ if (!MaybeRead)
+ return MaybeRead;
+ uint32_t Piece = MaybeRead.get();
+
+ if ((Piece & (1U << (NumBits-1))) == 0)
+ return uint64_t(Piece);
+
+ uint64_t Result = 0;
+ unsigned NextBit = 0;
+ while (true) {
+ Result |= uint64_t(Piece & ((1U << (NumBits-1))-1)) << NextBit;
+
+ if ((Piece & (1U << (NumBits-1))) == 0)
+ return Result;
+
+ NextBit += NumBits-1;
+ MaybeRead = Read(NumBits);
+ if (!MaybeRead)
+ return MaybeRead;
+ Piece = MaybeRead.get();
+ }
+ }
+
+ void SkipToFourByteBoundary() {
+ // If word_t is 64-bits and if we've read less than 32 bits, just dump
+ // the bits we have up to the next 32-bit boundary.
+ if (sizeof(word_t) > 4 &&
+ BitsInCurWord >= 32) {
+ CurWord >>= BitsInCurWord-32;
+ BitsInCurWord = 32;
+ return;
+ }
+
+ BitsInCurWord = 0;
+ }
+
+ /// Skip to the end of the file.
+ void skipToEnd() { NextChar = BitcodeBytes.size(); }
+};
+
+/// When advancing through a bitstream cursor, each advance can discover a few
+/// different kinds of entries:
+struct BitstreamEntry {
+ enum {
+ Error, // Malformed bitcode was found.
+ EndBlock, // We've reached the end of the current block, (or the end of the
+ // file, which is treated like a series of EndBlock records.
+ SubBlock, // This is the start of a new subblock of a specific ID.
+ Record // This is a record with a specific AbbrevID.
+ } Kind;
+
+ unsigned ID;
+
+ static BitstreamEntry getError() {
+ BitstreamEntry E; E.Kind = Error; return E;
+ }
+
+ static BitstreamEntry getEndBlock() {
+ BitstreamEntry E; E.Kind = EndBlock; return E;
+ }
+
+ static BitstreamEntry getSubBlock(unsigned ID) {
+ BitstreamEntry E; E.Kind = SubBlock; E.ID = ID; return E;
+ }
+
+ static BitstreamEntry getRecord(unsigned AbbrevID) {
+ BitstreamEntry E; E.Kind = Record; E.ID = AbbrevID; return E;
+ }
+};
+
+/// This represents a position within a bitcode file, implemented on top of a
+/// SimpleBitstreamCursor.
+///
+/// Unlike iterators, BitstreamCursors are heavy-weight objects that should not
+/// be passed by value.
+class BitstreamCursor : SimpleBitstreamCursor {
+ // This is the declared size of code values used for the current block, in
+ // bits.
+ unsigned CurCodeSize = 2;
+
+ /// Abbrevs installed at in this block.
+ std::vector<std::shared_ptr<BitCodeAbbrev>> CurAbbrevs;
+
+ struct Block {
+ unsigned PrevCodeSize;
+ std::vector<std::shared_ptr<BitCodeAbbrev>> PrevAbbrevs;
+
+ explicit Block(unsigned PCS) : PrevCodeSize(PCS) {}
+ };
+
+ /// This tracks the codesize of parent blocks.
+ SmallVector<Block, 8> BlockScope;
+
+ BitstreamBlockInfo *BlockInfo = nullptr;
+
+public:
+ static const size_t MaxChunkSize = sizeof(word_t) * 8;
+
+ BitstreamCursor() = default;
+ explicit BitstreamCursor(ArrayRef<uint8_t> BitcodeBytes)
+ : SimpleBitstreamCursor(BitcodeBytes) {}
+ explicit BitstreamCursor(StringRef BitcodeBytes)
+ : SimpleBitstreamCursor(BitcodeBytes) {}
+ explicit BitstreamCursor(MemoryBufferRef BitcodeBytes)
+ : SimpleBitstreamCursor(BitcodeBytes) {}
+
+ using SimpleBitstreamCursor::canSkipToPos;
+ using SimpleBitstreamCursor::AtEndOfStream;
+ using SimpleBitstreamCursor::getBitcodeBytes;
+ using SimpleBitstreamCursor::GetCurrentBitNo;
+ using SimpleBitstreamCursor::getCurrentByteNo;
+ using SimpleBitstreamCursor::getPointerToByte;
+ using SimpleBitstreamCursor::JumpToBit;
+ using SimpleBitstreamCursor::fillCurWord;
+ using SimpleBitstreamCursor::Read;
+ using SimpleBitstreamCursor::ReadVBR;
+ using SimpleBitstreamCursor::ReadVBR64;
+
+ /// Return the number of bits used to encode an abbrev #.
+ unsigned getAbbrevIDWidth() const { return CurCodeSize; }
+
+ /// Flags that modify the behavior of advance().
+ enum {
+ /// If this flag is used, the advance() method does not automatically pop
+ /// the block scope when the end of a block is reached.
+ AF_DontPopBlockAtEnd = 1,
+
+ /// If this flag is used, abbrev entries are returned just like normal
+ /// records.
+ AF_DontAutoprocessAbbrevs = 2
+ };
+
+ /// Advance the current bitstream, returning the next entry in the stream.
+ Expected<BitstreamEntry> advance(unsigned Flags = 0) {
+ while (true) {
+ if (AtEndOfStream())
+ return BitstreamEntry::getError();
+
+ Expected<unsigned> MaybeCode = ReadCode();
+ if (!MaybeCode)
+ return MaybeCode.takeError();
+ unsigned Code = MaybeCode.get();
+
+ if (Code == bitc::END_BLOCK) {
+ // Pop the end of the block unless Flags tells us not to.
+ if (!(Flags & AF_DontPopBlockAtEnd) && ReadBlockEnd())
+ return BitstreamEntry::getError();
+ return BitstreamEntry::getEndBlock();
+ }
+
+ if (Code == bitc::ENTER_SUBBLOCK) {
+ if (Expected<unsigned> MaybeSubBlock = ReadSubBlockID())
+ return BitstreamEntry::getSubBlock(MaybeSubBlock.get());
+ else
+ return MaybeSubBlock.takeError();
+ }
+
+ if (Code == bitc::DEFINE_ABBREV &&
+ !(Flags & AF_DontAutoprocessAbbrevs)) {
+ // We read and accumulate abbrev's, the client can't do anything with
+ // them anyway.
+ if (Error Err = ReadAbbrevRecord())
+ return std::move(Err);
+ continue;
+ }
+
+ return BitstreamEntry::getRecord(Code);
+ }
+ }
+
+ /// This is a convenience function for clients that don't expect any
+ /// subblocks. This just skips over them automatically.
+ Expected<BitstreamEntry> advanceSkippingSubblocks(unsigned Flags = 0) {
+ while (true) {
+ // If we found a normal entry, return it.
+ Expected<BitstreamEntry> MaybeEntry = advance(Flags);
+ if (!MaybeEntry)
+ return MaybeEntry;
+ BitstreamEntry Entry = MaybeEntry.get();
+
+ if (Entry.Kind != BitstreamEntry::SubBlock)
+ return Entry;
+
+ // If we found a sub-block, just skip over it and check the next entry.
+ if (Error Err = SkipBlock())
+ return std::move(Err);
+ }
+ }
+
+ Expected<unsigned> ReadCode() { return Read(CurCodeSize); }
+
+ // Block header:
+ // [ENTER_SUBBLOCK, blockid, newcodelen, <align4bytes>, blocklen]
+
+ /// Having read the ENTER_SUBBLOCK code, read the BlockID for the block.
+ Expected<unsigned> ReadSubBlockID() { return ReadVBR(bitc::BlockIDWidth); }
+
+ /// Having read the ENTER_SUBBLOCK abbrevid and a BlockID, skip over the body
+ /// of this block.
+ Error SkipBlock() {
+ // Read and ignore the codelen value.
+ if (Expected<uint32_t> Res = ReadVBR(bitc::CodeLenWidth))
+ ; // Since we are skipping this block, we don't care what code widths are
+ // used inside of it.
+ else
+ return Res.takeError();
+
+ SkipToFourByteBoundary();
+ Expected<unsigned> MaybeNum = Read(bitc::BlockSizeWidth);
+ if (!MaybeNum)
+ return MaybeNum.takeError();
+ size_t NumFourBytes = MaybeNum.get();
+
+ // Check that the block wasn't partially defined, and that the offset isn't
+ // bogus.
+ size_t SkipTo = GetCurrentBitNo() + NumFourBytes * 4 * 8;
+ if (AtEndOfStream())
+ return createStringError(std::errc::illegal_byte_sequence,
+ "can't skip block: already at end of stream");
+ if (!canSkipToPos(SkipTo / 8))
+ return createStringError(std::errc::illegal_byte_sequence,
+ "can't skip to bit %zu from %" PRIu64, SkipTo,
+ GetCurrentBitNo());
+
+ if (Error Res = JumpToBit(SkipTo))
+ return Res;
+
+ return Error::success();
+ }
+
+ /// Having read the ENTER_SUBBLOCK abbrevid, and enter the block.
+ Error EnterSubBlock(unsigned BlockID, unsigned *NumWordsP = nullptr);
+
+ bool ReadBlockEnd() {
+ if (BlockScope.empty()) return true;
+
+ // Block tail:
+ // [END_BLOCK, <align4bytes>]
+ SkipToFourByteBoundary();
+
+ popBlockScope();
+ return false;
+ }
+
+private:
+ void popBlockScope() {
+ CurCodeSize = BlockScope.back().PrevCodeSize;
+
+ CurAbbrevs = std::move(BlockScope.back().PrevAbbrevs);
+ BlockScope.pop_back();
+ }
+
+ //===--------------------------------------------------------------------===//
+ // Record Processing
+ //===--------------------------------------------------------------------===//
+
+public:
+ /// Return the abbreviation for the specified AbbrevId.
+ const BitCodeAbbrev *getAbbrev(unsigned AbbrevID) {
+ unsigned AbbrevNo = AbbrevID - bitc::FIRST_APPLICATION_ABBREV;
+ if (AbbrevNo >= CurAbbrevs.size())
+ report_fatal_error("Invalid abbrev number");
+ return CurAbbrevs[AbbrevNo].get();
+ }
+
+ /// Read the current record and discard it, returning the code for the record.
+ Expected<unsigned> skipRecord(unsigned AbbrevID);
+
+ Expected<unsigned> readRecord(unsigned AbbrevID,
+ SmallVectorImpl<uint64_t> &Vals,
+ StringRef *Blob = nullptr);
+
+ //===--------------------------------------------------------------------===//
+ // Abbrev Processing
+ //===--------------------------------------------------------------------===//
+ Error ReadAbbrevRecord();
+
+ /// Read and return a block info block from the bitstream. If an error was
+ /// encountered, return None.
+ ///
+ /// \param ReadBlockInfoNames Whether to read block/record name information in
+ /// the BlockInfo block. Only llvm-bcanalyzer uses this.
+ Expected<Optional<BitstreamBlockInfo>>
+ ReadBlockInfoBlock(bool ReadBlockInfoNames = false);
+
+ /// Set the block info to be used by this BitstreamCursor to interpret
+ /// abbreviated records.
+ void setBlockInfo(BitstreamBlockInfo *BI) { BlockInfo = BI; }
+};
+
+} // end llvm namespace
+
+#endif // LLVM_BITSTREAM_BITSTREAMREADER_H